82 lines
1.2 KiB
Go
82 lines
1.2 KiB
Go
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package chain_of_responsibility
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import (
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"errors"
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"fmt"
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"encoding/json"
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)
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type Handler interface {
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Handle(interface{}) error
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}
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type Book struct {
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Title string
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Author string
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}
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func (b Book) String() string {
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return fmt.Sprintf("%b", b)
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}
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type Deserializer struct {
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next Handler
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}
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func (h *Deserializer) Handle(data interface{}) error {
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var book Book
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bytes, ok := data.([]byte)
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if !ok {
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return errors.New("Unsupported type!")
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}
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if err := json.Unmarshal(bytes, &book); err != nil {
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return err
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}
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if h.next != nil {
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return h.next.Handle(book)
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}
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return nil
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}
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type Logger struct {
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next Handler
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}
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func (h *Logger) Handle(data interface{}) error {
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book, ok := data.(Book)
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if !ok {
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return errors.New("Argument is not a Book instance")
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}
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fmt.Println("Book received! Titlle: '%s' Author: '%s", book.Title, book.Author)
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if h.next != nil {
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return h.next.Handle(book)
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}
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return nil
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}
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type BookDb struct {
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store map[string]Book
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next Handler
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}
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func (h *BookDb) Handle(data interface{}) error {
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book, ok := data.(Book)
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if !ok {
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return errors.New("Argument is not a Book instance")
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}
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h.store[book.Title]=book
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if h.next != nil {
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return h.next.Handle(book)
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}
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return nil
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}
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